Engines are sometimes used to drive and support masses. For example, an engine can be used to drive a rotor of a single bearing generator. In such a setup, a first side of the rotor is supported by a bearing of the single bearing generator, while a second side of the rotor (opposite the first side of the rotor) is supported by the engine. Specifically, the second side of the rotor is supported by an end of a crankshaft of the engine. Unfortunately, when the crankshaft of the engine drives the rotor, movement of the crankshaft and the rotor causes the end of the crankshaft to orbit and/or vibrate. This orbiting and/or vibrating increases undesirable bending stresses within the crankshaft.
One way to reduce the orbiting and/or vibrating of the end of the crankshaft is to support the end of the crankshaft with a bearing. An example of this strategy is described in G.B. Patent No. 705,933 (the '933 patent) to Hallewell, which was published on Mar. 24, 1954. The '933 patent describes a rotor carried on a bracket, which is bolted directly to a flywheel. The flywheel is bolted to a crankshaft of an engine. Bending movement of the crankshaft is reduced by providing a crankshaft journal bearing placed close up to the flywheel.
Although the crankshaft journal bearing may reduce bending movement of the crankshaft as taught in the '933 patent, the combination of the crankshaft journal bearing and the bolts connecting the crankshaft to the flywheel may limit the crankshaft's ability to transmit to the flywheel large amounts of torque at high rotational speeds. This is because a strength (an ability to transmit torque) of the connection between the crankshaft and the flywheel of the '933 patent is proportional to the number of bolts of the connection. Although the number of bolts could be increased by increasing the diameter of the crankshaft (i.e., by increasing the connection area), the diameter of the crankshaft is limited by the rotational speed of the crankshaft. This is because the surface speed of the crankshaft is limited by the crankshaft journal bearing. Specifically, the surface speed of the crankshaft is limited by the crankshaft journal bearing because excessive surface speed can damage the crankshaft journal bearing. Since the diameter of the crankshaft and the rotational speed of the crankshaft are both proportional to the surface speed of the crankshaft, the diameter of the crankshaft and the rotational speed of the crankshaft are inversely proportional to each other when the surface speed of the crankshaft is held constant. Therefore, large diameters (capable of transmitting large amounts of torque) and high rotational speeds are mutually exclusive. In other words, the combination of the crankshaft journal bearing and the bolts connecting the crankshaft to the flywheel cannot, without damaging the crankshaft journal bearing, transmit to the flywheel some large amounts of torque at some high rotational speeds.
The disclosed combinations are directed to overcoming one or more of the problems set forth above and/or other problems in the art.